1. Field of the Invention
This invention relates to battery accommodating devices for use in cameras and other small size instruments and, more particularly, to battery accommodating devices with a cover for the opening of the battery chamber being pivotally supported near the battery chamber.
2. Description of the Prior Art
When a plurality of cylindrical batteries are to be incorporated within the case of an instrument of small size such as a camera, since the instrument body itself is small as compared with the required bulk and size of the battery accommodating device, a very serious problem arises as to how compact the configuration of the battery accommodating device can be made. In this connection, it should be noted that the degree of compactness of the battery accommodating device largely depends upon what form is assumed by the opening and closing mechanism of the cover provided on the opening portion of the battery accommodating device. For this reason, for such small size instruments in the past, there have been proposed a wide variety of opening and closing mechanisms for the cover in an attempt to obtain a more compact battery accommodating device.
As shown in FIG. 1, for example, the cover is constructed in the form of a slide plate 2 which is slidingly moved when being attached to and detached from the camera body 1. In another example shown in FIG. 2, the cover 5 is made of an elastic material such as synthetic resin and is provided with a resilient portion 5a near the pivoted side thereof, the opposite side of which is provided with a lock pawl 5b. Thus, the cover 5 is releasably locked in the closed position for the opening portion of the battery chamber 4 formed within the casing 3 of the instrument.
Certainly, the use of such configuration as shown in FIG. 1 or 2 leads to the provision of a compact and simple battery accommodating device. With the device of FIG. 1, however, since the cover 2 is removed from the instrument body 1 when the batteries are exchanged, there is some possibility of losing or misplacing the cover. Also, with the device of FIG. 2, when opening the cover 5, the operator must first release the cover 5 from the locking connection at the pawl 5b by pushing the cover 5 in the direction indicated by arrow A, while putting his fingernail in the recessed portion 5c and then raising up the cover 5 until the chamber is fully open. Thus, the handling of the cover 5 is very difficult to perform.
On the other hand, it is known in the art to provide a device of the construction as shown in FIG. 3 which overcomes the above-described handling difficulty. That is, formed within the instrument casing 6, is a battery chamber 7 with a cover 8 hinged at one side thereof through a spring 9, the opposite side of which is formed to a pawl 8a. This pawl 8a is made to cooperate with a lock member 10 which is constructed in isolation from the cover 8. This lock member 10 is urged by a spring 11 in a direction to bring the lock pawl 10a into engagement with the detent pawl 8a of the cover 8. As the locking is normally held, in releasing the cover 8 from the locking connection, the operator needs only to slidingly move the lock member 10 against the force of the bias spring 11. Then, the cover 8 is automatically opened by the power stored in the spring 9.
With such construction, it is possible that, unlike those arrangements of FIGS. 1 and 2, the loss of the cover is not encountered when the batteries are exchanged and only one touch is sufficient to effect opening of the cover. However, the device of FIG. 3 has a disadvantage that, besides the space which the battery chamber occupies, there must be created an additional space which the lock member 10 is intended to occupy and in which the lock member 10 can move. This takes away from achieving minimization of the bulk and size of the battery accommodating device.